rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5970/1:b..l P5824/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=12449, q=856383 ncpus=2)
task:syz-executor state:R running task stack:21544 pid:5824 tgid:5824 ppid:5823 task_flags:0x400100 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7109
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:102 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
RIP: 0010:unwind_next_frame+0x131c/0x2390 arch/x86/kernel/unwind_orc.c:494
Code: 00 00 00 00 49 01 ef 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 27 49 63 07 4c 01 f8 49 8d 4f 04 <4c> 39 e0 48 0f 46 e9 49 8d 47 fc 48 0f 47 d8 4d 0f 46 ef 48 39 dd
RSP: 0018:ffffc9000434f738 EFLAGS: 00000283
RAX: ffffffff82201eea RBX: ffffffff8fbd1fb0 RCX: ffffffff8fbd1fb4
RDX: ffffffff8fbd1fb0 RSI: ffffffff903d0734 RDI: ffffffff8be1b9e0
RBP: ffffffff8fbd1fb0 R08: 0000000000000001 R09: ffffffff8172aae5
R10: ffffc9000434f858 R11: ffffffff81acfd40 R12: ffffffff82201f76
R13: ffffffff8fbd1fb0 R14: ffffc9000434f808 R15: ffffffff8fbd1fb0
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf7/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1248 [inline]
__free_frozen_pages+0xc65/0xe60 mm/page_alloc.c:2706
discard_slab mm/slub.c:2717 [inline]
__put_partials+0x161/0x1c0 mm/slub.c:3186
put_cpu_partial+0x17c/0x250 mm/slub.c:3261
__slab_free+0x2f7/0x400 mm/slub.c:4513
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4148 [inline]
slab_alloc_node mm/slub.c:4197 [inline]
__kmalloc_cache_noprof+0x1be/0x3d0 mm/slub.c:4354
kmalloc_noprof include/linux/slab.h:905 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
alloc_pipe_info+0xe9/0x4d0 fs/pipe.c:798
get_pipe_inode fs/pipe.c:894 [inline]
create_pipe_files+0x8a/0x760 fs/pipe.c:926
__do_pipe_flags+0x4c/0x2d0 fs/pipe.c:983
do_pipe2+0x9c/0x170 fs/pipe.c:1034
__do_sys_pipe2 fs/pipe.c:1052 [inline]
__se_sys_pipe2 fs/pipe.c:1050 [inline]
__x64_sys_pipe2+0x5a/0x70 fs/pipe.c:1050
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd5c2d8d889
RSP: 002b:00007ffdbe3ed498 EFLAGS: 00000246 ORIG_RAX: 0000000000000125
RAX: ffffffffffffffda RBX: 0000555561a6bad0 RCX: 00007fd5c2d8d889
RDX: 0000000000000005 RSI: 0000000000000000 RDI: 00007ffdbe3ed4a8
RBP: 00007ffdbe3ed860 R08: 0000000000000007 R09: 0000555561a6def0
R10: be8dc1ba389931ff R11: 0000000000000246 R12: 00007ffdbe3ed8c0
R13: 0000555561a704e0 R14: 00007ffdbe3ed5e0 R15: 0000555561a6e4a8
task:syz.1.2 state:R running task stack:24952 pid:5970 tgid:5967 ppid:5843 task_flags:0x40044c flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6966
preempt_schedule+0xae/0xc0 kernel/sched/core.c:6990
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
zap_pte_range mm/memory.c:1765 [inline]
zap_pmd_range mm/memory.c:1827 [inline]
zap_pud_range mm/memory.c:1856 [inline]
zap_p4d_range mm/memory.c:1877 [inline]
unmap_page_range+0x3842/0x41c0 mm/memory.c:1898
unmap_single_vma mm/memory.c:1941 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:1985
exit_mmap+0x248/0xb50 mm/mmap.c:1284
__mmput+0x118/0x410 kernel/fork.c:1121
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x648/0x22e0 kernel/exit.c:952
do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
get_signal+0x125e/0x1310 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f502878eb69
RSP: 002b:00007f50295a5038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: 0000000000009f8d RBX: 00007f50289b6080 RCX: 00007f502878eb69
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f5028811df1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f50289b6080 R15: 00007ffdfdff02b8
rcu: rcu_preempt kthread starved for 4239 jiffies! g12449 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:R running task stack:27128 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7109
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:INIT_LIST_HEAD include/linux/list.h:37 [inline]
RIP: 0010:rcu_gp_fqs_loop+0x280/0x1540 kernel/rcu/tree.c:2054
Code: 00 00 48 8b 84 24 88 00 00 00 80 3c 30 00 4c 8d b4 24 c8 00 00 00 74 12 4c 89 f7 e8 1a a0 77 00 48 be 00 00 00 00 00 fc ff df <4c> 89 b4 24 c8 00 00 00 48 8b 84 24 80 00 00 00 80 3c 30 00 74 0d
RSP: 0018:ffffc90000157b60 EFLAGS: 00000246
RAX: 1ffff9200002af85 RBX: 0000000000000001 RCX: 0000000000000002
RDX: 0000000000000001 RSI: dffffc0000000000 RDI: ffffffff8be1ba40
RBP: ffffc90000157cb0 R08: ffffffff8fa0b3f7 R09: 1ffffffff1f4167e
R10: dffffc0000000000 R11: fffffbfff1f4167f R12: ffffffff8e144980
R13: ffffffff8e144530 R14: ffffc90000157c28 R15: 0000000000000000
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.16.0-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:lock_is_held_type+0x137/0x190 kernel/locking/lockdep.c:5948
Code: 01 75 44 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 4c 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 05 f9 02 36 07 <48> 3b 44 24 08 75 43 89 d8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90000006c28 EFLAGS: 00000206
RAX: 1a51038c9f649500 RBX: 0000000000000000 RCX: 1a51038c9f649500
RDX: 0000000000000100 RSI: ffffffff8db6fcc6 RDI: ffffffff8be1ba40
RBP: 00000000ffffffff R08: 0000000000000000 R09: ffffffff89d4ca86
R10: ffffc90000006da0 R11: fffff52000000dba R12: 0000000000000246
R13: ffffffff8de95280 R14: ffffffff8f509f08 R15: 0000000000000004
FS: 0000000000000000(0000) GS:ffff888125c57000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000027e430 CR3: 0000000027318000 CR4: 00000000003526f0
Call Trace:
lock_is_held include/linux/lockdep.h:249 [inline]
lockdep_rtnl_is_held+0x1b/0x40 net/core/rtnetlink.c:182
fib_lookup+0x17e/0x440 include/net/ip_fib.h:388
ip_route_output_key_hash_rcu+0x2fb/0x23a0 net/ipv4/route.c:2803
ip_route_output_key_hash+0x1b9/0x2e0 net/ipv4/route.c:2694
__ip_route_output_key include/net/route.h:169 [inline]
ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2921
ip_route_output_key include/net/route.h:179 [inline]
ip_route_me_harder+0x6b9/0xfe0 net/ipv4/netfilter.c:53
synproxy_send_tcp+0x359/0x6c0 net/netfilter/nf_synproxy_core.c:431
synproxy_send_client_synack+0x8bb/0xe20 net/netfilter/nf_synproxy_core.c:484
nft_synproxy_eval_v4+0x36e/0x560 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x345/0x570 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x409/0x1920 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:272 [inline]
NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:315
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:317
__netif_receive_skb_one_core net/core/dev.c:5977 [inline]
__netif_receive_skb+0x143/0x380 net/core/dev.c:6090
process_backlog+0x60e/0x14f0 net/core/dev.c:6442
__napi_poll+0xc4/0x480 net/core/dev.c:7414
napi_poll net/core/dev.c:7478 [inline]
net_rx_action+0x707/0xe30 net/core/dev.c:7605
handle_softirqs+0x283/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 53 de 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d d3 ad 21 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8de07d80 EFLAGS: 000002c2
RAX: 1a51038c9f649500 RBX: ffffffff81976918 RCX: 1a51038c9f649500
RDX: 0000000000000001 RSI: ffffffff8d982fba RDI: ffffffff8be1ba40
RBP: ffffffff8de07ea8 R08: ffff8880b8632f5b R09: 1ffff110170c65eb
R10: dffffc0000000000 R11: ffffed10170c65ec R12: ffffffff8fa0b3f0
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1bd2a50
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:749
default_idle_call+0x74/0xb0 kernel/sched/idle.c:117
cpuidle_idle_call kernel/sched/idle.c:185 [inline]
do_idle+0x1e8/0x510 kernel/sched/idle.c:325
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423
rest_init+0x2de/0x300 init/main.c:745
start_kernel+0x47d/0x500 init/main.c:1102
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288
common_startup_64+0x13e/0x147